1. Field of the Invention
The present invention relates to a display, a method of driving the display, and an electronic device. Specifically, it relates to a flat (flat panel type) display in which pixels each including an electro-optical device are arranged in a matrix, a method of driving the display, and an electronic device.
2. Description of the Related Art
In recent years, in the field of displays that display images, flat displays have rapidly become widespread, in which pixels (pixel circuits) including light emitting elements are arranged in a matrix. Flat displays, such as organic EL displays using an organic EL (Electro Luminescent) device, which utilizes the phenomenon of light emission upon application of an electric field to an organic thin film, have been developed, and are now being commercialized.
An organic EL device has low power consumption because it can be driven at a voltage of 10 V or less. Another feature is elimination of the use of a light source (backlight) commonly used in liquid crystal displays because the organic EL device is a self light emitting element. Further, since such an organic EL device responds very fast, its response rate being approximately several microseconds, afterimages during video display are not produced.
Similar to liquid crystal displays, an organic EL display can employ, as a driving scheme, a simple (passive) matrix scheme or an active matrix scheme. In recent years, displays utilizing an active matrix scheme have been actively developed in which active elements, such as insulated gate field effect transistors (generally, TFTs (Thin Film Transistors)), are placed in the pixel circuits.
In general, the I-V characteristics (current-voltage characteristics) of organic EL devices deteriorate as time passes (so-called deterioration over time). The threshold voltage Vth of a driving transistor and the mobility μ of a semiconductor thin film constituting a channel of a driving transistor (referred to below as mobility of a driving transistor) may change over time and vary per pixel due to variations in the manufacturing process.
In order to keep the light emission luminance of such an organic EL device constant without these influences, a configuration is employed so that each pixel circuit has a function compensating for variations in the characteristics of an organic EL device and correction functions of correcting variations in the threshold voltage Vth (referred to below as threshold correction) of a driving transistor and correcting variations in the mobility μ (referred to below as mobility correction) of a driving transistor (for example, refer to Japanese Unexamined Patent Application Publication No. 2006-133542).